PTPRC and acute lymphoblastic leukemia: Interestingly, at around the same dose of A23187 that induced B220 expression, 50% of HPB-ALL, Jurkat, BW5147 and EL-4 cells died (Annexin V and PI staining, Figure 5, see Cell viability) or shifted from region R2 to R1 on the FSC vs. SSC dot plots (Figure 5, see Cell morphology).